So, some guidance would be helpful.

$\displaystyle ydx+(2xy-e^{-2y})dy = 0

$

$\displaystyle \frac{1-2y}{-y}$

$\displaystyle e^{^-{\int \frac{1}{y}-2}} $

$\displaystyle \frac{e^{2y}}{y}$ is the integrating factor.

And upon solving, the answer is: $\displaystyle C = xe^{2y}-ln|y|$?